1. Field of the Invention
The present invention relates to an apparatus for cleaning a vacuum drum that is used for conveying gummed labels.
2. Discussion of Background
Vacuum drums are routinely used in machines that apply labels to containers. A vacuum drum is an open-ended cylinder with a plate on one end and a multiplicity of holes along the perimeter. The holes are in fluid communication with vacuum ports on the end plate. A vacuum is applied to the vacuum ports, which in turn creates suction at the holes along the perimeter of the drum. The vacuum picks up and holds the labels to the drum perimeter as the drum rotates.
In the process of applying labels to containers, the vacuum drum is located adjacent an adhesive station where an adhesive is applied to the labels. The vacuum drum is rotated to transport the labels in front of an adhesive station where adhesive is applied to the labels. In many cases, the adhesive station coats not only the labels, but also spreads adhesive onto the perimeter of the vacuum drum which will eventually plug the perimeter holes. Consequently, over an extended period of time the capability of the vacuum drum to securely hold the labels is reduced.
In order to unplug the holes on the vacuum drum, workers manually clean the drum using handtools. Cleaning the holes is a time consuming task, taking several hours during which labeling operations are suspended. Moreover, it is very difficult to fully unplug the holes and bring the vacuum drum back to its initial capability.
Consequently, there is need for an automated vacuum drum cleaner that can clean different sizes of vacuum drums in order to reduce the time spent cleaning vacuum drums.